<!-- 快速创建
    header+(main>section+aside)+footer      快速创建语义标签
-->




<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>进阶页面框架</title>
    <style>
        /* 通用样式 */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        .left {
            float: left;
        }

        .right {
            float: right;
        }

        .clear::after {
            content: " ";
            display: block;
            clear: both;
        }

        ul,
        ol,
        li {
            list-style: none;
        }

        a {
            text-decoration: none;
            color: inherit;
        }

        .w100 {
            width: 100%;
        }

        .w70 {
            width: 70%;
        }

        .w60 {
            width: 60%;
        }

        .w50 {
            width: 50%;
        }

        .w40 {
            width: 40%;
        }

        .w30 {
            width: 30%;
        }

        /* 头部 */
        header {
            height: 60px;
            line-height: 60px;
            background-color: lightblue;
        }

        header nav {
            width: 1100px;
            margin: 0 auto;
        }

        header nav .nav-item {
            width: 120px;
            text-align: center;
        }

        header nav .active,
        header nav .nav-item:hover {
            background-color: pink;
            color: white;
        }


        /* 主体 */
        main {
            width: 1100px;
            margin: 0 auto;
            background-color: lightgray;
            position: relative;
        }

        main .news {
            background-color: lightgreen;
        }
        main .imgs {
            background-color: lightcyan;
            margin-left: 30px;
        }
        main section .item {
            text-indent: 2em;
            height: 150px;
            border-bottom: 2px dotted black;
        }

        main aside {
            background-color: lightblue;
        }

        main aside ul {
            list-style: none;
        }

        main aside li {
            height: 40px;
            line-height: 20px;
            text-align: center;
            padding: 10px 5px;
        }

        main aside li+li {
            border-top: 2px solid lightcyan;
        }

        main .gotop{
           width: 50px;
           height: 50px;
           text-align: center;
           line-height: 25px;
           font-size: 20px;
           background-color: lightblue;
           border-radius: 5px;
           position: absolute;
           left: 50%;
           margin-left: 550px;
           bottom: 160px;

        }

        /* 脚部 */
        footer{
            background-color: #001e50;
        }
        footer .content{
            width: 1100px;
            margin: 0 auto;
        }
        footer .content a{
            width: 220px;
            height: 20px;
            text-align: center;
            line-height: 20px;
            padding: 30px;
            display: block;
            float: left;

        }
    </style>
</head>

<body>
    <header>
        <nav class="clear">
            <ul class="left">
                <li class="left nav-item active"><a href="">首页</a></li>
                <li class="left nav-item"><a href="">服务</a></li>
                <li class="left nav-item"><a href="">下载</a></li>
            </ul>

            <ul class="right">
                <li class="left nav-item"><a href="">登录</a></li>
                <li class="left nav-item"><a href="">注册</a></li>
            </ul>





        </nav>
    </header>


    <main class="clear">
        <section class="left w30 news">
            <div class="item">段落1</div>
            <div class="item">段落2</div>
            <div class="item">段落3</div>
            <div class="item">段落4</div>
            <div class="item">段落5</div>
        </section>

        <section class="left w30 imgs">
            <div class="item">段落1</div>
            <div class="item">段落2</div>
            <div class="item">段落3</div>
            <div class="item">段落4</div>
            <div class="item">段落5</div>
        </section>

        <aside class="right w30">
            <ul>
                <li><a href="">链接1</a></li>
                <li><a href="">链接2</a></li>
                <li><a href="">链接3</a></li>
                <li><a href="">链接4</a></li>
                <li><a href="">链接5</a></li>
            </ul>
        </aside>
        <div class="gotop">顶部</div>
    </main>

    <footer>
        <div class="content clear">
            <a href="">链接1</a>
            <a href="">链接2</a>
            <a href="">链接3</a>
            <a href="">链接4</a>
            <a href="">链接5</a>
            <a href="">链接6</a>
            <a href="">链接7</a>
            <a href="">链接8</a>
            <a href="">链接9</a>
            <a href="">链接10</a>

        </div>

    </footer>

</body>

</html>